1. Field of the Invention
The invention relates to an assistant apparatus and method for a vehicle in reverse motion, and more particularly to an assistant apparatus and method for a vehicle driver to drive the vehicle in reverse by means of a camera taking a rearward image from the vehicle and a display showing an estimated reverse motion locus of the vehicle superimposed onto the image when the driver parks the vehicle and drives the car into a turnout temporarily.
2. Description of the Related Arts
Conventionally, methods of assisting the parallel parking and pulling in parking such as into a garage for an inexperienced driver are well known. In Japanese Patent Laid-open Publication No. H07-17328, a CCD camera and a distance sensor for measuring the distance are provided on a vehicle body and the environment around the vehicle is detected to show the driver a bird""s eye view of the surrounding scene from the vehicle on the display in the vehicle.
In a Japanese Patent Laid-open Publication No. S59-201082, a method for detecting the steering angle by a steering sensor and calculating the steering wheel angle for output to the display is disclosed. In another Japan Patent Laid-open Publication No. H08-2357, a method for measuring a distance between the vehicle and an obstacle (especially an already parked vehicle next to a parking space) by a distance sensor for object detection provided on the rear of the vehicle and detecting a position for starting turning of the wheels by the maximum steering angle in accordance with the distance to inform the driver of the timing for initiating steering operation is disclosed.
However, the conventional methods mentioned above require detecting the obstacles around the vehicle using various sensing technologies, which complicates a system for transaction. In addition, the method for measuring and informing the driver of the distance between the vehicle and the obstacle by the distance sensor does not necessarily assist parking especially when another vehicle is not parked next to the parking space and when obstacles suddenly occur such as a person suddenly approaching the vehicle during a parking operation.
It is, therefore, an object of the present invention to obviate the above drawbacks of the prior arts.
It is a further object of the present invention to provide an assistant apparatus and method for a vehicle in reverse motion which enables an inexperienced driver to execute the parking operation with no difficulties and worries and which appropriately assists the parking operation.
According to the present invention, the assistant apparatus includes a camera taking the images rearwardly from the vehicle during the parking operation, an indication means showing the image from the camera as a rearward image, a vehicle condition detecting means detecting the vehicle condition, and an estimated locus calculating means calculating an estimated locus for vehicle driving based on the information from the vehicle condition detecting means and the vehicle performance to show the estimated locus overlapping with the rearward image on the indication means, wherein the technical means further includes a locus fixing means showing a first estimated locus in accordance with the steering angle at an initial stage and fixing the first estimated locus at a predetermined condition, a target locus setting means setting the first estimated locus as a target locus when the first estimated locus is fixed by the locus fixing means, and a guiding means showing a second estimated locus varied in accordance with the change of the steering angle during the parking operation on the indication means to guide the second estimated locus to the target locus.
The effects of the assistant apparatus for the vehicle in reverse motion are as follows. Indicating the first estimated locus in accordance with the steering angle at an initial stage of the parking operation, fixing the first estimated locus under a predetermined condition (it is fixed by the driver) to set the first estimated locus as the target locus, showing the second estimated locus varied in accordance with the steering angle during the parking operation on the indication means to enable guidance of the second estimated locus to the fixed target locus, operating the steering wheel by guiding the second estimated locus to agree with the standardized target locus. This does not require any complicated operation under any parking circumstances. For instance, since it is not necessary to maintain the steering wheel nervously for a predetermined period during the parallel parking, even an inexperienced driver is able to carry out the parking easily.
In this case, when the direction is informed based on the information from the vehicle condition detecting means and the target locus, the guiding means calculates the difference from the target locus based on the information from the fixed target locus and the vehicle condition detecting means (such as the condition of the shift lever, the steering condition, and traveling condition), which provides appropriate directions in accordance with the calculated difference or the positional relations between the fixed and target locus to provide an apparatus appropriately assisting the parking operation.
The predetermined condition can be set as follows:
When there are no obstacles in the range of the first estimated locus and when the first estimated locus is indicated in the direction which the driver intends to park, the first estimated locus is fixed to park the vehicle based on such conditions after confirming the driver""s intention to park and confirming the safety for the parking operation.
According to the present invention, an assistant apparatus for a vehicle in reverse motion includes a camera taking a rearward image from the vehicle during the reverse motion, a detecting means for detecting a vehicle""s reverse motion, a calculating means for calculating an estimated reverse motion locus based on the vehicle condition and vehicle characteristics, and a display showing the latest estimated reverse motion locus as a present locus and one of the estimated reverse motion loci at a specific timing as a target locus, both the current and the target locus being superimposed onto the rearward image.
Further, according to the present invention, an assistant apparatus for a vehicle in reverse motion includes a camera continuously taking a rearward image from the vehicle during the reverse motion, a detecting means for detecting a vehicle condition of reverse motion, a calculating means for calculating an estimated reverse motion locus based on the vehicle condition and vehicle characteristics, and a display showing the estimated reverse motion locus superimposed onto the rearward image, wherein one of the estimated reverse motion loci at a specific timing is fixed as a target locus on the display, and the estimated reverse motion locus is continuously shown on the display even after the target locus is fixed.
Furthermore, according to the present invention, an assistant method for a vehicle in reverse motion includes a first step for continuously taking a rearward image from the vehicle during the reverse motion, a second step for continuously detecting a vehicle condition of reverse motion, a third step for continuously calculating an estimated reverse motion locus based on the vehicle condition and vehicle characteristics, and a fourth step for continuously showing the estimated reverse motion locus superimposed onto the rearward image, a fifth step for fixing one of the estimated reverse motion loci at a specific timing as a target locus on the display, and a sixth step for further continuously showing the estimated reverse motion locus on the display even after the target locus is fixed.